head to head
Call of Duty: World at War asks more than Grand Theft Auto: San Andreas, and the gap is execution.

Execution · Practiced Mastery
A gritty WWII Call of Duty that introduced the Zombies mode.

Optimization · Practiced Mastery
A sprawling open-world crime epic with RPG-style character stats across a whole state.
Call of Duty: World at War leans Execution (Practiced Mastery); Grand Theft Auto: San Andreas leans Optimization (Practiced Mastery).
Call of Duty: World at War leans clearly harder on execution.
Call of Duty: World at War
Twitch gunfights in fast multiplayer lobbies
Grand Theft Auto: San Andreas
Flying school and drive-bys need decent hands
Call of Duty: World at War leans clearly harder on reads.
Call of Duty: World at War
Human opponents reward positioning prediction
Grand Theft Auto: San Andreas
Gang AI is scripted, never adaptive
Call of Duty: World at War leans a little harder on variance, though the gap is small.
Call of Duty: World at War
Random lobbies, spawns, and zombie waves
Grand Theft Auto: San Andreas
Territory wars and traffic add light randomness
Grand Theft Auto: San Andreas leans a little harder on optimization, though the gap is small.
Call of Duty: World at War
Perk loadouts and map control are learnable
Grand Theft Auto: San Andreas
Stats, gym, weapon skill, and routes reward systematic play
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.